Potassium Vapor Topping Cycle. Technical Progress Report, October 1, 1977--December 31, 1977

摘要

The potassium vapor topping cycle is a concept for increasing the efficiency of the Rankine vapor cycle by raising the peak temperature by employing a potassium vapor cycle with a turbine inlet temperature of 1500 to 1600 exp 0 F (815 to 870 exp 0 C) in which the waste heat rejected from the condensing potassium vapor is transferred to boiling water and steam in a conventional steam cycle. An efficiency of about 50% is calculated for this cycle with a natural circulation potassium boiler fired by gas or oil. A DOE program is underway at ORNL to build a full-scale potassium boiler tube bundle and burner module and test it with water and then potassium. Operation of the boiler with potassium was initiated at the beginning of this quarter. Problems with plugging of the fill tank and condenser vent lines were encountered in the early runs. These problems were corrected and a boiling test run was made at a power level of about 1.9 x 10 exp 6 Btu/hr. A small potassium leak occurred in the liquid level indicator sheath, making it necessary to replace the level indicator with an alternate level indicator system that makes use of two argon bubbler tubes. The new level indicator was installed and the boiler was nearly ready for operation at the end of the quarter. (ERA citation 03:049920)